JP2000193946A - Liquid crystal device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely embody both of a color display and a black and white display with one liquid crystal panel. SOLUTION: This liquid crystal device has a common substrate 3a and segment substrate 3b facing each other across liquid crystals 6. The segment substrate 3b has colored layers 13 and transparent layers 16 within the same plane. The colored layers 13 and the transparent layers 16 are formed to the same height with each other and consequently, a cell gap G is maintained constant over the entire surface of the liquid crystal panel 1A. Consequently, the driving conditions of the liquid crystals are maintained under adequate conditions over the entire surface of the liquid crystal panel 1A and, therefore, both of the color display and the black and white display may be surely made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling characters or numerals,
The present invention relates to a liquid crystal device that displays an image such as a picture. The present invention also relates to an electronic device including the liquid crystal device.

[0002]

2. Description of the Related Art At present, liquid crystal devices are widely used in electronic devices such as portable telephones and portable information terminals. In many cases, the liquid crystal device is used to display information such as characters, numbers, and patterns.

This liquid crystal device generally has a liquid crystal sandwiched between a pair of substrates, and controls the orientation of the liquid crystal by controlling a voltage applied to the liquid crystal, thereby modulating light incident on the liquid crystal. I do. Some liquid crystal devices display information such as characters in color. In such a liquid crystal device, a color filter is provided on one surface of a pair of substrates. In a conventional liquid crystal device having a structure using a color filter, the color filter is provided on the entire surface of the substrate in many cases.

As a conventional liquid crystal device, there is known a liquid crystal device having a structure in which a color filter is provided in a partial area of the entire area of a plane of a liquid crystal panel as disclosed in, for example, Japanese Patent Application Laid-Open No. 10-298291. I have.

[0005]

With respect to a conventional liquid crystal device having a structure in which a color filter is provided on the entire surface of a substrate,
There is a problem that both a color display area and a black and white display area cannot be displayed on the surface of one liquid crystal panel.

Further, with respect to a conventional liquid crystal device having a structure in which a color filter is provided in a partial area of a liquid crystal panel, by setting an area where a color filter is not provided, it seems that black and white display can be performed in addition to color display. . However, in reality, the black and white display cannot be performed properly. It is considered that the reason is that a difference occurs in the cell gap between the region where the color filter is provided and the region where the color filter is not provided, so that the driving condition regarding the liquid crystal is different between those regions.
For example, in a plurality of regions where the cell gap is different, the appropriate amount of the chiral agent mixed into the liquid crystal changes, so that the liquid crystal cannot be properly driven in all the regions.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to surely realize both color display and monochrome display with one liquid crystal panel.

[0008]

(1) In order to achieve the above object, a liquid crystal device according to the present invention has a pair of substrates opposed to each other with a liquid crystal interposed therebetween, and at least one of the substrates is the same. A coloring layer and a transparent layer are provided in a plane, and the coloring layer and the transparent layer have substantially the same height.

Here, "substantially" means that even when a slight error occurs due to a manufacturing error or the like, such an error is included when the same effect can be obtained.

According to the liquid crystal device having the above structure, even when a colored layer is provided in a partial region of a substrate and a colored layer is not provided in another region, a transparent layer having the same height as the colored layer is provided in that region. Since the layers are provided, the cell gap can be maintained uniformly over the entire surface of the liquid crystal panel. As a result, the driving conditions for the liquid crystal can be maintained under the same conditions between the colored layer and the non-colored layer, so that one liquid crystal panel can realize both color display and monochrome display without any problem.

(2) Regarding the liquid crystal device, there are known a single-sided display type liquid crystal device that performs display from only one side of a pair of substrates, a double-sided display type liquid crystal device that performs display from both of a pair of substrates, and the like. ing. In a double-sided display type liquid crystal device, a display mode in which color display is performed on one surface and black-and-white display is performed on the opposite surface may be adopted. If the present invention having the above structure is applied to such a liquid crystal device, color display is performed from one substrate through a colored layer,
Further, black and white display can be performed from the other substrate through the transparent layer. In this case, by using the configuration of the present invention, a constant cell gap can be maintained between the colored layer and the transparent layer,
Therefore, both color display and monochrome display can be clearly formed.

(3) In the liquid crystal device of the double-sided display system as described above, for example, a polarizing plate is provided on each of the outer surfaces of a pair of substrates, and one of the outer surfaces of the polarizing plate provided on one of the substrates is provided. A first reflection layer provided in a partial region, and a second reflection layer provided in a region other than a region facing the first reflection layer on an outer surface of the polarizing plate provided on the other substrate. it can.

(4) Further, in the liquid crystal device of the double-sided display system as described above, for example, a reflective polarizer is provided on each outer surface of a pair of substrates, and a polarizing plate is further provided outside the reflective polarizer. Can be configured by When this reflective polarizer is used, a color display corresponding to the colored layer can be displayed on both the front and back surfaces, and a monochrome display corresponding to the transparent layer can be displayed on both the front and back surfaces.

The above-mentioned reflective polarizer will be described as follows. While a general polarizing plate has a function of transmitting linearly polarized light directed in a certain direction and not transmitting other polarized light by absorption or dispersion, the reflective polarizer has a function of transmitting linearly polarized light in a certain direction. And transmits other linearly polarized light. In particular, linearly polarized light perpendicular to the transmitted polarization axis is totally reflected.

Such a reflective polarizer is disclosed in an internationally filed international application (international application number WO95 / 17692 or W.
O95 / 27919), a polarization separation film having a structure in which a number of thin films are stacked, a polarization separation plate having a structure in which a (1/4) λ plate is disposed on both sides or one side of a cholesteric liquid crystal layer, A polarization separation member (SID 92 DIGEST, pp. 427 to 42) that separates reflected polarized light and transmitted polarized light using Brewster's angle.
9) or a polarization separating member using a hologram.

This reflective polarizer has a multilayer structure formed by alternately laminating two types of layers A and B, as shown in FIG. 5, for example. Among the two layers adjacent to each other in the stacking direction, the refractive index in one direction is equal between the two layers, and the refractive index in the direction perpendicular thereto is set to be different between the two layers. It has a change.

In FIG. 5, when considering the three orthogonal directions of XYZ, the two layers A and B are formed in a multilayer state by, for example, extrusion molding, and are further formed in one direction (for example, the X direction).
, And not in the other direction (ie, the Y direction). That is, the X-axis direction is the stretching direction, and the Y-axis direction is the transverse direction to it. B
The material has a refractive index n _S (eg, n _S = 1.64), which does not change substantially with the stretching process. On the other hand, the material A has a characteristic that the refractive index changes by the stretching process. For example, when a sheet made of the material A is stretched in a uniaxial direction, the sheet has one refractive index n _AX (for example, n _AX = 1.88) in the stretching direction (that is, the X direction);
Different refractive indices n _{AY in the} lateral direction (ie, Y direction)
(For example, n _AY = 1.64).

If the laminated structure shown in FIG. 5 made of the materials A and B is stretched in the X direction, a large refractive index difference Δn = 1.88-1.64 = 0.24 occurs in the stretching direction. On the other hand, in the Y direction perpendicular to the direction, the refractive index difference Δn = 1.64-1.64 = 0 between the A and B layers, and there is no difference in the refractive index. Due to such optical characteristics, when light enters the reflective polarizer, the polarized component (a) in the direction of the transmission axis E of the incident light passes through the reflective polarizer. On the other hand,
The polarization component (b) of the incident light in the direction of the light absorption axis F faces the refractive index difference Δn, and is therefore reflected at that part.

Further, the layer thicknesses t1, t2, A, B,
At t3,……… the dimensions are changed little by little,
Therefore, as shown in FIG. 6, light (b-1), (b-2),... Having different wavelengths can be reflected at the boundary surface between the layers. That is, A, B having different layer thicknesses
With two types of multilayer structures, it is possible to efficiently reflect light including all types of wavelengths.

Incidentally, the layer thicknesses t1, t2, t3,
... Are combined so as to reflect light of all wavelengths, the finally obtained reflected light becomes white light. On the other hand, the layer thicknesses t1, t2, t3,.
Is set to an appropriate combination, only light of a desired wavelength, that is, light of a desired color can be selectively reflected by the reflective polarizer.

(5) In the liquid crystal device of the double-sided display system as described above, for example, a first reflective layer is provided in a partial region on the inside or outside of the first substrate of the pair of substrates. Providing a first polarizing plate in a region of the outer surface of the first substrate where the first reflective layer is not provided, and providing the first polarizing plate on the inner or outer surface of the second substrate facing the first substrate. A second reflective layer is provided facing the one polarizing plate, and a second reflective layer is provided on the outer surface of the second substrate so as to face the first reflective layer.
It can be configured by providing a polarizing plate.

(6) Next, the electronic apparatus according to the present invention
In an electronic apparatus including a liquid crystal device and a housing for accommodating the liquid crystal device, the liquid crystal device includes the above-described liquid crystal devices having various configurations. As such an electronic device, for example, a portable information terminal, a mobile phone, or the like can be considered.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows an embodiment of a liquid crystal panel which is a main part of a liquid crystal device according to the present invention. The liquid crystal device is formed by attaching ancillary equipment such as a liquid crystal driving IC and a lighting device to the liquid crystal panel 1A. The liquid crystal panel 1A of the present embodiment is a simple matrix type liquid crystal panel that does not use an active element.

This liquid crystal panel 1A is composed of a pair of substrates whose periphery is joined by a sealing material 2, that is, a common substrate 3.
a and the segment substrate 3b. The spacing between these substrates, the so-called cell gap G, is maintained at a constant size by the spacer 4, and the liquid crystal 6 is sealed in the cell gap.

The common substrate 3a has a transparent material substrate 7a, and a common electrode 8a is patterned into a predetermined shape on the inner surface of the material substrate 7a, and an alignment film 9a is further formed thereon.
Is formed. On the outer surface of the material substrate 7a, a polarizing plate 11a is attached to almost the entire surface of the material substrate 7a, and further, a first reflection layer 12a is provided in a partial region of the surface of the material substrate 7a.

The segment substrate 3b facing the common substrate 3a has a transparent material substrate 7b. This material substrate 7b
A so-called color filter 13 is formed in a partial region of the inner surface of the color filter 1.
A transparent layer 16 is formed in the same plane as 3. The color filter 13 is formed in a region facing the first reflection layer 12a formed on the common substrate 3a facing the color filter 13, and is provided between the color portions 17 arranged in a dot matrix form. And the black matrix 18 arranged in the matrix. The color portion 17 is R (red),
It is formed by arranging each color of G (green) and B (blue) in a mosaic, delta, stripe, or the like.

The transparent layer 16 is provided on the inner surface of the segment substrate 3b and in a region where the color filter 13 is not provided, and a transparent portion 19 made of a transparent material is provided between the transparent portions 19. It is formed by the black matrix 18 arranged. The transparent layer 16 is formed such that its height is the same as the height of the color filter 13.

A smooth layer 14 is formed on the color filter 13 and the transparent layer 16, a segment electrode 8b is patterned thereon in a predetermined shape, and an alignment film 9b is formed thereon.

Material substrate 7 constituting segment substrate 3b
A polarizing plate 11b is adhered to the outer surface of the material substrate 7b, and a second reflection layer 12b is provided in a partial region of the surface of the material substrate 7b. The second reflection layer 12b is provided corresponding to the transparent layer 16, and as a result, the first reflection layer 12b on the common substrate 3a side is formed.
It is provided corresponding to a region where the reflective layer 12a is not provided. That is, the first reflection layer 12a and the second reflection layer 12b
Are provided so as to complement each other in a plan view.

In the above configuration, the material substrates 7a and 7
b is formed of a transparent material such as glass or plastic. The common electrode 8a and the segment electrode 8b are made of, for example, ITO (Indium Tin Oxide:
(Indium tin oxide). The alignment films 9a and 9b are formed of, for example, polyimide or the like. As is well known, the polarizing plates 11a and 11b are polarization separating elements having a function of transmitting linearly polarized light directed in a certain direction and not transmitting other polarized light by absorption or the like.

Since the first reflection layer 12a and the second reflection layer 12b are formed of a non-transparent material, in the liquid crystal panel 1A of the present embodiment, the front side of each reflection layer 12a and 12b is the observation side, and the observer LCD panel 1A from arrow C direction
Observe and confirm the image. That is, in this embodiment, 1
Images can be displayed on both front and back sides of one liquid crystal panel 1A.

Specifically, as shown in FIG. 2, the light reflected by the first reflection layer 12a and the second reflection layer 12b is
The image is displayed by the contrast between the light absorbed by 1a and 11b. In particular, color filter 1
Color display is performed in the area CL provided with 3, while black and white display is performed in the area MN provided with the transparent layer 16.

In this embodiment, the height of the color filter 13 and the height of the transparent layer 16 are set to be equal to each other, so that the cell gap G is maintained uniformly over the entire surface of the liquid crystal panel 1A. For this reason, the conditions required when driving the liquid crystal, such as the appropriate amount of the chiral agent, can be kept constant over the entire surface of the liquid crystal panel 1A, and therefore both the color display and the monochrome display can be clearly displayed under the appropriate conditions. it can.

(Second Embodiment) FIG. 3 shows another embodiment of the liquid crystal panel which is the main part of the liquid crystal device according to the present invention. In this figure, the same members as those shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The liquid crystal panel 1B according to the present embodiment is different from the liquid crystal panel 1A shown in FIG.
The reflective polarizers 21a and 21b are provided on the entire area of the outer surface of the material substrate 7a constituting the segment substrate 3b and the entire area of the outer surface of the material substrate 7b constituting the segment substrate 3b, and the outside of the reflective polarizers 21a and 21b. This means that the polarizing plates 22a and 22b are adhered to the entire surface, respectively. As the reflective polarizers 21a and 21b,
A film-like reflective polarizer having the structure shown in FIGS. 5 and 6 can be used.

In the present embodiment, as shown in FIG. 4, regardless of which of the region CL where the color filter 13 is provided and the region MN where the transparent layer 16 is provided,
By contrast between light reflected by the reflective polarizers 21a and 21b and light transmitted through the liquid crystal panel 1B, an image can be displayed on both sides of the entire surface of the liquid crystal panel 1B. Of course, color display is performed in the area CL where the color filter 13 is provided, while black and white display is performed in the area MN where the transparent layer 16 is provided.

Also in this embodiment, the color filter 1
3 and the transparent layer 16 are set to be equal to each other, so that the cell gap G is maintained uniformly over the entire surface of the liquid crystal panel 1B. Therefore, conditions required for driving the liquid crystal, such as an appropriate amount of the chiral agent, can be maintained constant over the entire surface of the liquid crystal panel 1B,
Therefore, both color display and monochrome display can be clearly displayed under appropriate conditions.

(Third Embodiment) FIG. 7 shows still another embodiment of the liquid crystal panel which is the main part of the liquid crystal device according to the present invention. In this figure, the same members as those shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

The liquid crystal panel 1C according to the present embodiment differs from the liquid crystal panel 1A shown in FIG. 1 in the following points. That is, the inner electrode 23a is formed on the inner surface of the common substrate 3a with Al (aluminum) or the like corresponding to the region CL where the color filter 13 is provided, and the segment substrate corresponding to the region MN where the transparent layer 16 is provided. Similarly, an inner electrode 23b is formed on the inner surface of 3b by using Al or the like.
Then, the polarizing plate 11b is attached to the color filter region CL on the outer surface of the segment substrate 3b, and further, the polarizing plate 11a is attached to the transparent layer region MN on the outer surface of the common substrate 3a.

In this embodiment, since the inner electrodes 23a and 23b are partially provided for the respective substrates 3a and 3b, a step corresponding to the inner electrodes 23a and 23b is formed in the cell gap G. However, also in this embodiment, since the color filter 13 and the transparent layer 16 are set at the same height as each other, the size of the cell gap G itself is different from the liquid crystal panel 1.
It is kept constant over the entire surface of C.

In the embodiment shown in FIG. 1, two polarizing plates 11a and 11b are present in both the color filter region CL and the transparent layer region MN. On the other hand, in the present embodiment shown in FIG. 7, one polarizing plate 11b exists in the color filter region CL, and one polarizing plate 11a also exists in the transparent layer region MN. According to this panel structure, attenuation of light passing through this panel can be reduced by an amount corresponding to the number of polarizing plates reduced by one, and thus a bright display can be obtained.

In this embodiment, the inner electrodes 23a and 23b
Is the observation side, and the observer can check the display from both front and back sides according to the arrow C. In the present embodiment, FIG.
As shown in FIG.
In L, the light is reflected by the inner surface electrode 23a and
The color display is performed by the contrast between the light transmitted through the polarizing plate 11b and the light absorbed by the polarizing plate 11b. On the other hand, in the region MN where the transparent layer 16 is provided, black-and-white display is performed by the contrast between the light reflected by the inner electrode 23b and transmitted through the polarizing plate 11a and the light absorbed by the polarizing plate 11a. .

Also in this embodiment, the color filter 1
3, and the height of the transparent layer 16 are set to be equal to each other, so that the cell gap G is maintained uniformly over the entire surface of the liquid crystal panel 1C. For this reason, the conditions required for driving the liquid crystal, such as the appropriate amount of the chiral agent, can be maintained constant over the entire surface of the liquid crystal panel 1C.
Therefore, both color display and monochrome display can be clearly displayed under appropriate conditions.

(Fourth Embodiment) FIG. 9 shows a portable information terminal which is an embodiment of an electronic apparatus according to the present invention. The portable information terminal 26 has a first housing 27 and a second housing 28. The second housing 28 can be opened and closed with respect to the first housing 27 as shown in FIGS.
A liquid crystal device 29 is housed inside the housing 28. The liquid crystal device 29 can be configured using, for example, any one of the liquid crystal panel 1A (FIG. 1), the liquid crystal panel 1B (FIG. 3), and the liquid crystal panel 1C (FIG. 7).

As shown in FIG. 9, an opening, that is, a window 31 is formed in the surface of the second housing 28, and a part of the surface side of the liquid crystal device 29, for example, the transparent layer region MN is exposed to the outside through the window 31. I do. As shown in FIG. 10, an opening, that is, a window 32 is also formed on the back surface of the second housing 28, and a part of the back surface side of the liquid crystal device 29, for example, the color filter region CL is exposed to the outside through the window 32. I do. Reference numeral 33 indicates a keyboard switch.

If 7-segment display is performed in the transparent layer area MN and dot matrix display is performed in the color filter area CL, 7-segment black and white display is performed through the window 31 with the portable information terminal 26 closed. Visible. Further, the color display of the dot matrix display can be visually recognized through the window 32 with the portable information terminal 26 opened.

(Other Embodiments) The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and various modifications may be made within the scope of the invention described in the claims. Can be modified.

For example, each of the liquid crystal panels shown in FIGS. 1, 3 and 7 is a double-sided display type liquid crystal panel having a structure in which display is performed on both front and back sides. It can be applied to a liquid crystal panel.

The present invention is not limited to a simple matrix type liquid crystal panel, but includes a TFT (Thin Film Transistor),
The present invention is also applicable to an active matrix type liquid crystal panel having a structure in which a non-linear element such as a TFD (Thin Film Diode) is used as an active element.

The electronic device according to the present invention is not limited to a portable information terminal, but may be a mobile phone or any other electronic device.

[0050]

According to the liquid crystal device and the electronic apparatus of the present invention, in a liquid crystal device having a structure in which a colored layer is provided on a portion of the substrate surface of a liquid crystal panel, a transparent layer is provided in a region where no colored layer is provided, and Since the height of the transparent layer is the same as the height of the coloring layer, the size of the cell gap can be made uniform over the entire surface of the liquid crystal panel. As a result, both color display and monochrome display can be reliably performed by one liquid crystal panel. realizable.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of a liquid crystal device according to the present invention.

FIG. 2 is a sectional view schematically showing a display state of the liquid crystal device of FIG.

FIG. 3 is a sectional view showing a main part of another embodiment of the liquid crystal device according to the present invention.

4 is a cross-sectional view schematically illustrating a display state of the liquid crystal device of FIG.

FIG. 5 is a perspective view schematically showing an example of the structure of a reflective polarizer.

FIG. 6 is a diagram for explaining the function of the reflective polarizer of FIG. 5;

FIG. 7 is a sectional view showing a main part of still another embodiment of the liquid crystal device according to the present invention.

8 is a cross-sectional view schematically showing a display state of the liquid crystal device of FIG.

FIG. 9 is a perspective view showing a portable information terminal which is an embodiment of the electronic device according to the present invention.

FIG. 10 is a perspective view showing a state where a housing of the portable information terminal of FIG. 9 is opened.

[Explanation of symbols]

 1A, 1B, 1C Liquid crystal panel 2 Sealing material 3a Common substrate 3b Segment substrate 4 Spacer 6 Liquid crystal 7a, 7b Material substrate 8a Common electrode 8b Segment electrode 9a, 9b Alignment film 11a, 11b Polarizer 12a First reflective layer 12b Second reflection Layer 13 Color filter (colored layer) 16 Transparent layer 17 Color portion 18 Black matrix 19 Transparent portion 21a, 21b Reflective polarizer 22a, 22b Polarizer 23a, 23b Inner electrode E Transmission axis F Absorption axis G Cell gap

Continued on the front page (72) Inventor Seichi Iino 3-3-5 Yamato, Suwa-shi, Nagano F-term in Seiko Epson Corporation (reference) 2H089 HA15 HA33 HA40 QA14 TA12 TA15 TA17 2H090 HA04 HC12 HD03 LA02 LA06 LA09 LA15 LA20 2H091 FA02Y FA08X FA08Z FA14Z FA35Y FD05 FD06 GA13 LA15

Claims (6)

[Claims] In a liquid crystal device having a pair of substrates opposed to each other with a liquid crystal interposed therebetween, at least one of the substrates has a coloring layer and a transparent layer in the same plane, and the coloring layer and the transparent layer are substantially the same. A liquid crystal device having a height. 2. The liquid crystal device according to claim 1, wherein the liquid crystal device is a double-sided display type liquid crystal device that displays an image from both of the pair of substrates, and an image formed through the coloring layer is transmitted from at least one of the substrates to the outside. A liquid crystal device, wherein an image displayed and formed through the transparent layer is displayed externally from at least the other substrate. 3. The polarizing plate according to claim 2, wherein a polarizing plate provided on each outer surface of the pair of substrates, a first reflective layer provided on a partial region of one of the outer surfaces of the polarizing plates, A liquid crystal device comprising: a second reflection layer provided in a region other than a region facing the first reflection layer on the other outer surface of the polarizing plates. 4. The liquid crystal according to claim 2, further comprising: a reflective polarizer provided on each of outer surfaces of the pair of substrates; and a polarizer provided outside the reflective polarizer. apparatus. 5. The method according to claim 2, wherein a first reflection layer provided on a partial region of a surface inside or outside the first substrate of the pair of substrates, and an outer surface of the first substrate. A first polarizing plate provided in a region where the first reflective layer is not provided; and a first polarizing plate provided on a surface inside or outside a second substrate facing the first substrate so as to face the first polarizing plate. A liquid crystal device, comprising: a second reflective layer provided on a substrate; and a second polarizing plate provided on an outer surface of the second substrate so as to face the first reflective layer. 6. An electronic apparatus having a liquid crystal device and a housing for accommodating the liquid crystal device, wherein the liquid crystal device is configured by the liquid crystal device according to at least one of claims 1 to 5. Electronic equipment characterized by the following.